Blower Fan

ABSTRACT

A blower fan includes a housing having a lateral wall defining a compartment. The housing includes an air inlet and an air outlet both in communication with the compartment. An impeller mounted in the compartment includes a hub and blades mounted on the hub. A first plane including opposite first and second end edges in the air outlet is parallel to and spaced from a second plane including a center of the hub. The compartment of the housing includes an air outlet section and a pressure accumulating section on opposite sides of the second plane. The air outlet section is located between the first and second planes. The lateral wall of the housing includes at least one air guiding hole located in the pressure accumulating section. At least one air guiding tube includes an outlet end and an inlet end coupled to the at least one air guiding hole.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a blower fan and, more particularly, to a blower fan including air guiding tubes.

2. Description of the Related Art

Conventional blower fans include a housing having an axial air inlet and a side air outlet. An impeller is rotatably mounted in the housing for drawing in air currents that are concentrated before exiting the side air outlet to a heat source. In use, the blower fans must be mounted adjacent the heat source with the side air outlet aligned with the heat source to assure temperature lowering of the heat source.

Currently available electronic products may have several heat sources such as the main board, the central processing unit, the display card, etc located in different locations. However, the conventional blower fans can only perform heat dissipation for the heat sources adjacent the side air outlet. A solution to this is increasing the number of the blower fans that leads to inevitable increase in the costs. In another approach, the housing of the blower fan is provided with several air outlets or an external air guiding tube for dissipating heat generated by heat sources in different locations.

FIG. 1 shows a blower fan 7 including a substrate 71 on which an impeller unit 72 and a lateral wall 73 are provided. A pressure accumulating channel 74 is formed on an inner side of the lateral wall 73 and includes two ends each having a radial air outlet 75. The substrate 71 defines an axial air inlet 76 perpendicular to the radial air outlets 75. The impeller unit 72 draws in air currents via the axial air inlet 76. The air currents exit the radial air outlets 75 under the centrifugal force created during operation of the impeller unit 72 to dissipate heat generated by heat sources in different locations. An example of such a blower fan 7 is disclosed in Taiwan Patent Publication No. 516668. However, the heat sources can not always locate adjacent the radial air outlets 75. Thus, the blower fan 7 provides limited utility.

FIG. 2 shows a blower fan 8 including a side air outlet 81 and an air guiding tube 82 coupled to the side air outlet 81. The air guiding tube 82 can be coupled to a heat source 84 via a heat pad 83. By such an arrangement, the blower fan 8 not only dissipates heat by the side air outlet 81 but also generates air currents that are guided by the air guiding tube 82 to the heat source 84 distant to the blower fan 8. The blower fan 8 generally includes a pressure accumulating section for increasing the wind pressure of the air currents generated by the blower fan 8. An example of such a blower fan 8 is disclosed in Taiwan Patent Publication No. 200517816. However, an end of the air guiding tube 82 coupled to the side air outlet 81 of the blower fan is not in the pressure accumulating section, such that the amount of air provided through the air guiding tube 82 is limited, failing to effectively lower the temperature of the heat source 84 and having unsatisfactory heat dissipating effect.

FIG. 3 discloses a blower fan 9 including a side air outlet 92. An air guiding tube 91 includes a first end 911 coupled to blower fan 9 and a second end 912 extending toward a heat source 93. In operation, the heat generated by the heat source 93 flow from the second end 912 to the first end 911 while the blower fan 9 generates air currents. The side air outlet 92 of the blower fan 9 can be utilized to dissipate heat generated by another heat source. An example of such a blower fan 9 is disclosed in Taiwan Patent Publication No. 200528011. However, the first end 911 of the air guiding tube 91 is not in the pressure accumulating section of the blower fan 9. Furthermore, the heat generated by the heat source 93 must flow from the second end 912 to the first end 911, such that the heat dissipating effect provided by the air guiding tube 91 is still unsatisfactory.

SUMMARY OF THE INVENTION

An objective of the present invention is to provide a blower fan with increased air output.

Another objective of the present invention is to provide a blower fan capable of dissipating heat of heat sources in different locations.

The present invention fulfills the above objectives by providing, in a preferred form, a blower fan including a housing having a lateral wall defining a compartment. The housing further includes an air inlet and an air outlet both in communication with the compartment. The air outlet includes opposite first and second end edges. The housing defines a first plane passing the first and second end edges. An impeller is rotatably mounted in the compartment of the housing. The impeller includes a hub and a plurality of blades mounted on an outer periphery of the hub. The impeller defines a second plane including a center of the hub. The second plane is parallel to and spaced from the first plane. At least one air guiding tube includes an inlet end and an outlet end. The compartment of the housing includes an air outlet section and a pressure accumulating section on opposite sides of the second plane. The air outlet section is located between the first and second planes. The lateral wall of the housing includes at least one air guiding hole located in the pressure accumulating section. The inlet end of the at last one air guiding tube is coupled to the at least one air guiding hole.

The present invention will become clearer in light of the following detailed description of illustrative embodiments of this invention described in connection with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The illustrative embodiments may best be described by reference to the accompanying drawings where:

FIG. 1 shows an elevational view of a conventional blower fan.

FIG. 2 shows an exploded, perspective view of another conventional blower fan.

FIG. 3 shows an exploded, perspective view of a further conventional blower fan.

FIG. 4 shows an exploded, perspective view of a blower fan of a first embodiment according to the preferred teachings of the present invention.

FIG. 5 shows a cross sectional view of the blower fan of FIG. 4.

FIG. 6 shows a cross sectional view of a blower fan of a second embodiment according to the preferred teachings of the present invention.

FIG. 7 shows a cross sectional view of a blower fan of a third embodiment according to the preferred teachings of the present invention.

FIG. 8 shows a cross sectional view of a lower fan of a fourth embodiment according to the preferred teachings of the present invention.

All figures are drawn for ease of explanation of the basic teachings of the present invention only; the extensions of the figures with respect to number, position, relationship, and dimensions of the parts to form the preferred embodiments will be explained or will be within the skill of the art after the following teachings of the present invention have been read and understood. Further, the exact dimensions and dimensional proportions to conform to specific force, weight, strength, and similar requirements will likewise be within the skill of the art after the following teachings of the present invention have been read and understood.

Where used in the various figures of the drawings, the same numerals designate the same or similar parts. Furthermore, when the terms “first”, “second”, “inner”, “outer”, “end”, “section”, “centrifugal”, and similar terms are used herein, it should be understood that these terms have reference only to the structure shown in the drawings as it would appear to a person viewing the drawings and are utilized only to facilitate describing the invention.

DETAILED DESCRIPTION OF THE INVENTION

A blower fan of a first embodiment according to the preferred teachings of the present invention is shown in FIGS. 4 and 5 and generally includes a housing 1, an impeller 2, and an air guiding tube 3. The housing 1 can be mounted in a desired location of an electronic product, such as a side of a main board inside a computer. The impeller 2 is rotatably mounted in the housing 1 to generate enough amount of air for heat dissipating purposes. The air guiding tube 3 is coupled to the housing 1 for dissipating heat generated by heat sources 4 in different locations of the electronic product.

Specifically, the housing 1 includes a lateral wall 11 defining a compartment 111. The housing 1 further includes an air inlet 12 and an air outlet 13 that are in communication with the compartment 111. The air outlet 13 includes opposite first and second end edges 131 and 132. The housing 1 defines a first plane P1 passing the first and second end edges 131 and 132. A cover 14 is mounted to the lateral wall 11 of the housing 1 and includes an opening 141 aligned with the air inlet 12. Air currents generated by the impeller 2 can flow through the opening 141 and the air inlet 12 into the compartment 111 of the housing 1. The housing 1 can include at least one auxiliary air inlet preferably aligned with the air inlet 12.

The impeller 2 is rotatably mounted in the compartment 111 and includes a hub 21 and a plurality of blades 22. The impeller 2 defines a second plane P2 including a center of the hub 21. The second plane P2 is parallel to and spaced from the first plane P1. The blades 22 are mounted to an outer periphery of the hub 21 for driving the air currents to the air outlet 13 and the air guiding tube 3.

More specifically, the compartment 111 is divided into an air outlet section 111 a and a pressure accumulating section 111 b by defining the first and second planes P1 and P2. The air outlet section 111 a is located between the first and second planes P1 and P2. The pressure accumulating section 111 b and the air outlet section 111 a are located on opposite sides of the second plane P2. The lateral wall 11 includes an air guiding hole 15 in the pressure accumulating section 111 b for coupling the air guiding tube 3.

The air guiding tube 3 includes an inlet end 31 and an outlet end 32. The inlet end 31 is coupled to the air guiding hole 15 of the housing 1 and in communication with the compartment 111. Namely, the inlet end 31 is located in the pressure accumulating section 111 b. The outlet end 32 extends away from the housing 1 for guiding the air currents to the heat source 4.

With reference to FIG. 5, in use, the air outlet 13 faces a heat source 4, and the length of the air guiding tube 3 allows it to extend to another heat source 4 with the outlet end 32 of the air guiding tube 3 facing the other heat source 4. The impeller 2 draws in air currents, and the centrifugal force created during operation of the impeller 2 drives the air currents to the heat sources 4 via the air guiding tube 3 and the air outlet 13. Thus, the blower fan according to the teachings of the present invention can dissipate heat generated by heat sources 4 in different locations.

Since the inlet end 31 of the air guiding tube 3 is in the pressure accumulating section 111 b, the wind pressure of the air currents drawn in by the impeller 2 via the air inlet 12 can be accumulated in the pressure accumulating section 111 b to provide a larger wind pressure. Thus, the air currents driven by the blades 22 can flow more easily along an inner face of the lateral wall 11 of the housing 1 to the heat source 4 after passing through the air guiding tube 3. Thus, the air guiding tube 3 provides more amount of air by the larger wind pressure to dissipate the heat generated by the heat source 4, enhancing the overall heat dissipating effect.

More specifically, with reference to FIG. 5, an inner wall S1 of the air guiding tube 3 according to the teachings of the present invention is preferably tangent to the inner face S2 of the lateral wall 11 in the pressure accumulating section 111 b. Thus, the air currents driven by the blades 22 flowing along the inner wall S2 of the lateral wall 11 of the housing 1 encounters less resistance, so that the air guiding tube 3 can provide more amount of air for heat dissipating purposes.

The housing 1 of the blower fan according to the teachings of the present invention can include one or more air guiding holes 15 cooperating one or more air guiding tubes 3 according to needs. Furthermore, the blower fan according to the teachings of the present invention can utilize various types of the air guiding tubes 3.

In a preferred form shown in FIG. 6, the lateral wall 11 of the housing 1 includes an air guiding hole 15 located in the pressure accumulating section 111 b. The air guiding tube 3 further includes a plurality of branch tubes 33 between the inlet end 31 and the outlet end 32. The branch tubes 33 extend to additional heat sources 4. Thus, the air guiding tube 3 can proceed with heat dissipation for more heat sources 4.

In another preferred form shown in FIG. 7, the lateral wall 11 of the housing 1 includes an air guiding hole 15 located in the pressure accumulating section 111 b. Furthermore, there are two air guiding tubes 3 provided for two heat sources 4. The inlet end 31 of each air guiding tube 3 is coupled to the air guiding hole 15. The outlet end 32 of each air guiding tube 3 extends toward one of the heat sources 4. Thus, the air guiding tubes 3 can proceed with heat dissipation for the heat sources 4 in different locations. The air guiding tubes 3 can be integrally formed with each other as a single continuous monolithic member as desired.

In another preferred form shown in FIG. 8, the lateral wall 11 of the housing 1 includes two air guiding holes 15 located in the pressure accumulating section 111 b. Furthermore, there are two air guiding tubes 3 provide for a plurality of heat sources 4. The inlet end 31 of each air guiding tube 3 is coupled to one of the air guiding holes 15. Each air guiding tube 3 includes one or more branch tubes 33 between the inlet end 31 and the outlet end 32. Thus, the air guiding tubes 3 can proceed with heat dissipation for many heat sources 4, providing enhanced utility.

According to above, by locating the air inlet ends 31 of the air guiding tubes 3 in the pressure accumulating section 111 b, the air currents driven by the impeller 2 can flow through the air guiding tubes 3 to the heat sources 4 under less resistance, providing excellent heat dissipation and enhancing the heat dissipating effect.

The air guiding tubes 3 according to the teachings of the present invention can provide more amount of air for dissipating heat generated by a plurality of heat sources 4 while providing air output via the air outlet 13, of the housing 1. Thus, the amount of outputted air is increased.

The blower fan according to the teachings of the present invention can proceed heat dissipation for a heat source 4 via the air outlet 13 of the housing 1 as well as for a plurality of heat sources 4 distant to the blower fan by using at least one air guiding tube 3, providing enhanced utility.

Thus since the invention disclosed herein may be embodied in other specific forms without departing from the spirit or general characteristics thereof, some of which forms have been indicated, the embodiments described herein are to be considered in all respects illustrative and not restrictive. The scope of the invention is to be indicated by the appended claims, rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein. 

1. A blower fan comprising: a housing including a lateral wall defining a compartment, with the housing further including an air inlet and an air outlet both in communication with the compartment, with the air outlet including opposite first and second end edges, with the housing defining a first plane passing the first and second end edges; an impeller rotatably mounted in the compartment of the housing, with the impeller including a hub and a plurality of blades mounted on an outer periphery of the hub, with the impeller defining a second plane including a center of the hub, with the second plane parallel to and spaced from the first plane; and at least one air guiding tube including an inlet end and an outlet end, with the compartment of the housing including an air outlet section and a pressure accumulating section on opposite sides of the second plane, with the air outlet section located between the first and second planes, with the lateral wall of the housing including at least one air guiding hole located in the pressure accumulating section, with the inlet end of said at last one air guiding tube coupled to said at least one air guiding hole.
 2. The blower fan as claimed in claim 1, with said at least one air guiding tube including an inner wall tangent to an inner face of the lateral wall of the housing in the pressure accumulating section.
 3. The blower fan as claimed in claim 1, with said at least one air guiding tube further including a plurality of branch tubes between the inlet end and the outlet end.
 4. The blower fan as claimed in claim 1, with said at least one air guiding hole including an air guiding hole, with said at least one air guiding tube including two air guiding tubes, and with the inlet ends of the two air guiding tubes coupled to the air guiding hole.
 5. The blower fan as claimed in claim 3, with said at least one air guiding hole including an air guiding hole, with said at least one air guiding tube including two air guiding tubes, and with the inlet ends of the two air guiding tubes coupled to the air guiding hole.
 6. The blower fan as claimed in claim 1, with said at least one air guiding hole including two air guiding holes located in the pressure accumulating section, with said at least one air guiding tube including two air guiding tubes, and with the inlet end of each of the two air guiding tubes coupled to one of the two air guiding holes.
 7. The blower fan as claimed in claim 3, with said at least one air guiding hole including two air guiding holes located in the pressure accumulating section, with said at least one air guiding tube including two air guiding tubes, and with the inlet end of each of the two air guiding tubes coupled to one of the two air guiding holes. 